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427 knocking

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Old Sep 12, 2012 | 01:15 PM
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Default 427 knocking

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I have a 427 and missed 3rd and over revved it and a few weeks later it started knocking. Had to replace the valve train and lifters on the passenger side. Once I had everything replaced it is still making a knocking sound that sounds like it's coming maybe from the cam? I'm not a mechanic and I've had a lot of different story's on what is wrong. Just looking for some other opinions.
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Old Sep 12, 2012 | 01:20 PM
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If you over revved it, there's a possibility that it's a bent pushrod. You said that you replaced the valve train on the passenger side, is the "knock" coming from the driver's side now?

Last edited by KevinR; Sep 13, 2012 at 04:12 PM.
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Old Sep 12, 2012 | 01:27 PM
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No it's coming from the center of the engine and none of the push rods look bent. I've laid them side by side and rolled them all no wobble or anything.
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Old Sep 12, 2012 | 01:29 PM
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Not trying to be an *** here, but why did you only change the passenger side lifters? Also, what is your set up?
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Old Sep 12, 2012 | 02:24 PM
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Just financial reasons. And I didn't see any problems with the other lifters. You thinking its a lifter problem? And it's just a regular 427 set up with a fast 92 intake no other mods to the motor.
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Old Sep 12, 2012 | 02:32 PM
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Just financial reasons. And I didn't see any problems with the other lifters. You thinking its a lifter problem? And it's just a regular 427 set up with a fast 92 intake no other mods to the motor.
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Old Sep 12, 2012 | 04:05 PM
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Originally Posted by Arondwreck12
Just financial reasons. And I didn't see any problems with the other lifters. You thinking its a lifter problem? And it's just a regular 427 set up with a fast 92 intake no other mods to the motor.
It's hard to say. Can you post a video of it?
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Old Sep 13, 2012 | 11:45 AM
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If you over-revved it, you might have spun a bearing and have a rod knocking. If you continue to run it without inspecting the bottom end, you can kiss that engine goodbye,
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Old Sep 14, 2012 | 04:07 PM
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Drain the oil into a clean container and inspect for any signs of copper bearing material.
Perform a leak-down test on all cylinders which will tell you if you have a bent valve

By the way, where are you located?
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Old Sep 14, 2012 | 09:08 PM
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Crazy idea, but exhaust leaks can sound like "knocking" sometimes
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